The Supercar Registry - Need a little price help

I have located a 69 427/435 horse motor (aftermarket intake and carb) with a turbo 400, that I think I am going to use for the car. When I am done I think I will be in to this for low 20ish, and that includes paying myself back for the value of donated wheel/tires, correct power disc brake set up, etc. So the next question is, what is a very nice, never rusted, original interior 68 obviously non original drivetrain, camaro worth? I don't like to be upside down on these projects by alot on these projects? Oh, and while this is going to be a very nice car, I am not taking it apart and doing a complete restoration so the underside is going to be driver quality for sure. Thanks for the help.